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    <title>Document</title>
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        color: red;
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    <ul>
        <li>1</li>
        <li>2</li>
        <li>3</li> 
        <li ><a href="#" >我是dml</a></li>       
    </ul>
    <ul class="nav">
        <li>4</li>
        <li>5</li>
        <li>6</li>
        <li><a href="#"></a>我是dml</li>
    </ul>
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